What is meralgia paresthetica due to?
**Core Concept**
Meralgia paresthetica is a condition characterized by numbness, tingling, and burning pain in the outer part of the thigh, typically caused by compression of the lateral femoral cutaneous nerve. This nerve supplies sensation to the skin of the lateral thigh.
**Why the Correct Answer is Right**
The lateral femoral cutaneous nerve is a branch of the lumbar plexus, which arises from the L2 and L3 nerve roots. Compression of this nerve can occur due to various reasons such as tight clothing, obesity, or direct trauma to the nerve. The compression leads to irritation of the nerve, resulting in symptoms of numbness, tingling, and burning pain in the affected area.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as meralgia paresthetica is not caused by a vascular issue. While vascular conditions can cause similar symptoms, the underlying pathophysiology is different.
**Option B:** This option is incorrect as meralgia paresthetica is not a form of peripheral neuropathy. While peripheral neuropathy can cause similar symptoms, meralgia paresthetica is a specific condition caused by compression of the lateral femoral cutaneous nerve.
**Option C:** This option is incorrect as meralgia paresthetica is not a form of referred pain. Referred pain occurs when pain is perceived at a location other than the site of the painful stimulus. Meralgia paresthetica, on the other hand, is a localized condition caused by compression of a specific nerve.
**Clinical Pearl / High-Yield Fact**
A common cause of meralgia paresthetica is wearing tight clothing, particularly tight pants or belts, which can compress the lateral femoral cutaneous nerve. This is a classic exam trap, as it highlights the importance of considering the patient's occupation and lifestyle when diagnosing this condition.
**Correct Answer: C. Compression of the lateral femoral cutaneous nerve.**